docs: add managed connection pooling to docs (#2425)

## Description

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🛠️ Fixes #<issue_number_goes_here>

docs/en/resources/sources/alloydb-pg.md

@@ -194,6 +194,15 @@ Use environment variable replacement with the format ${ENV_NAME}
 instead of hardcoding your secrets into the configuration file.
 {{< /notice >}}
 
+### Managed Connection Pooling
+
+Toolbox automatically supports [Managed Connection Pooling][alloydb-mcp]. If your AlloyDB instance has Managed Connection Pooling enabled, the connection will immediately benefit from increased throughput and reduced latency.
+
+The interface is identical, so there's no additional configuration required on the client. For more information on configuring your instance, see the [AlloyDB Managed Connection Pooling documentation][alloydb-mcp-docs].
+
+[alloydb-mcp]: https://cloud.google.com/blog/products/databases/alloydb-managed-connection-pooling
+[alloydb-mcp-docs]: https://cloud.google.com/alloydb/docs/configure-managed-connection-pooling
+
 ## Reference
 
 | **field** | **type** | **required** | **description**                                                                                                          |

docs/en/resources/sources/cloud-sql-pg.md

@@ -195,6 +195,15 @@ Use environment variable replacement with the format ${ENV_NAME}
 instead of hardcoding your secrets into the configuration file.
 {{< /notice >}}
 
+### Managed Connection Pooling
+
+Toolbox automatically supports [Managed Connection Pooling][csql-mcp]. If your Cloud SQL for PostgreSQL instance has Managed Connection Pooling enabled, the connection will immediately benefit from increased throughput and reduced latency.
+
+The interface is identical, so there's no additional configuration required on the client. For more information on configuring your instance, see the [Cloud SQL Managed Connection Pooling documentation][csql-mcp-docs].
+
+[csql-mcp]: https://docs.cloud.google.com/sql/docs/postgres/managed-connection-pooling
+[csql-mcp-docs]: https://docs.cloud.google.com/sql/docs/postgres/configure-mcp
+
 ## Reference
 
 | **field** | **type** | **required** | **description**                                                                                                          |